The vast majority of TA personnel join their local TA centre, which is home to an Independent Unit. The unit's role varies, depending on the region, and is likely to fall into one of the following categories: combat, communications, medical, engineering or logistics. Most TA personnel prefer to join the unit nearest to their home, whatever the unit's role, but you can choose a different unit so long as you are prepared to travel to the TA centre for training evenings and weekends.

Upon joining an Independent Unit you train first and foremost as a soldier. You can then choose to focus on developing specific trades and skills relevant to your particular unit. If you already have a particular skill, you may be able to join a Specialist Unit.

By joining an Independent Unit you commit yourself to a minimum of 27 days training per year, including weekly training evenings, the occasional weekend and a two-week annual camp. Specialist Units require less commitment.